Plant material (e.g. cereal grains) is often used as feedstock for the production of target chemicals in a biorefinery. The plant material is typically milled and further processed to convert starch and/or fiber into fermentable sugars. The sugars are then converted by microorganisms, such as bacteria, yeast or both, in a fermentation process to produce a fermentation product. The fermentation product includes the target chemical and other materials which may include for example, water and other components such as oils, proteins, and residual carbohydrates including starches, sugars, and fiber. The target chemical is separated from the fermentation product and the other components are often collected as one or more co-products. A valuable class of co-products is oil.
The separation of oil from the fermentation product and other components is difficult because a portion of the oil remains bound or trapped in the other components such e.g. in the germ and fiber. What are needed are systems and methods that increase the release of bound or trapped oil in biorefinery process streams to facilitate oil separation and thereby increase oil yield. Obtaining additional oil from otherwise recalcitrant sources, particularly in ethanol production processes, are desirable to increase the overall value of the production process.